Combined torque changer and variable speed transmission



P. H. MARSELL May 8, 1951 COMBINED TORQUE CHANGER AND VARIABLE SPEED TRANSMISSION 2 Sheets-Sheet 1 Filed June 28, 1949 JNVENTOR. Paa/ f7. Waive/Z y 1951 P. H. MARSELL 2,552,010

COMBINED TORQUE CHANGER AND VARIABLE SPEED TRANSMISSION Filed June 28, 1949 2 Sheets-Sheet 2 ,2 JNVENTOR.

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Patented May 8, 1951 uni-Tee ES PAT ENT OFFICE COMBINED :TORQUE. CHANGE R2 AND VARIABLE SPEED TRANSMISSION Z'OIaiins. 1'5 This?invention.relates:tortransmissiondevices, and [more particularly to. a variable speed trans-. mission; of the? fluid type.

A main object of; the. invention is :tofprovide .atnovel: and improved combined. torque changer and-v variable.- speed: transmission. of the. fluid type-whichisverysimple-in construction, reliable in: operation, adapted; to provide: high startingztorque for starting aloadfrom a cone dition' of rest,. and providing, selective speeds from the. initial; condition up to the final condition, wherein. the drivenshaftof the transmissionrotates at thesame. speed asthe. driving shaft.

A.- further, object. of the. invention is to provide. an. improvedjvariable speed. transmission of.-.the. fluid type. especially adapted for, use on motor vehicles or. the like, said transmission involving. only. a few parts, being compact in sizarelatively light' in. weight; and" preventing coasting: of. the vehicle when the speed of .the vehicle tends to exceed" the driving spjeecl afforded by the driving shaft thereof. 7

Further objects andi'ad'van'tages offthe inverrtion will' become apparent from the following description and claims; and from. the ac companying drawings; wherein:

Figure" 1" is a vertical" cross-sectional view taken. through a transmission unit constructed in" accordance with the present invention;

Figure'Z is a cross sectiona'l view' taken on line "2-2"of Figure 1;

Figure 3 isacross-sectional view taken on-line 3"3- of Figure" 2;

Figure 4 is an" enlarged detail view; partly inxcross==section, ofon'e of the speed responsive pump outlet valve elements"- employed inthe transmission unit" of Figure 1;

Figure 5' isan enlarged cross sectional-detail view' of one" of the" inlet checkwalves" employed with" the" gear pump of" the transmissionunit of Figure" 1",

Eigure. 6' is a cross' section'al 'view taken on line 6 -5" ofFi'gure- 1:

Referring to..-.the drawings-,- I l designates the driven shaft and'l2 designates the driving shaft. Scuredto the end of driving shaft 12- is' the flywheel l3. Secured to flywheel reas ure cy lindrical hOIlSilI'gqg Me? Theihousings M has an endwall l5 through the. center of which shaft II. rotatably and sealingly passes.

Diametri'callysecured" to en'df'. wall 152' is. the diametrically elongated pump housing I6; the transverse wall' of said housing being. formed withopposedb'earing blocks. llj. l1. Journaled in the respective bearing blocks I? and the 0pposingiportions'offlywheel" l 3" are the respective shafts I85 I8: Each-shaft l8 carries asmall pl'a-netarygear" I-9 and a large planetary gear 202- Tfi'einnerend of drivenshaft I I has a re- 2,. ducedportion 2| which. isijournaledaxially. in flywheel |3.- Secured-on shaft II adjacent the reduced portionzl is a-large sungear 22 which meshes with the small planetary pinio-ns or gears [9-, l9.

Rotatably mountedon shaft I l and extending rotatablythrough the pump. housing 16'. is a sleeve member zsdntegrally formed at itsinner end with. a sunpinion Zimeshingwiththe large planetary gears 20, 20. Keyed on sleeve 23-withinhousing I6 is apumpgear 25. Journaled in the outer portions of housing 10 are respective additional pump gears 26 meshing with gear 25.

Thelonger side walls of pump housing I6 are designated respectively-at 21; 2 1". sidewall 21) is formed between gears 25- and-ZB with an outlet passage 23 to which is connectedlanoutlet conduit 29. Side wall 2'! isformed between gears 25* and 26' withian inlet passage. wand mounted on the outer side of wall 21 isa check valve 3! communicating with passage 30, as shown:in.- Figure. 5, and allowing 'fluid. to enter saidpassage from outside. the housing It, but preventing flow of fluidoutwardly from the housing. Opposite inlet passage the opposite side wall 21 is formed with an outlet passage 23 to which is connected an outlet conduitZQ. Opposite outlet passage 28 the side wall 23" is formed-with an inlet passage 351, and the side wallZ-l is. provided with an inlet check valve 3| similar to check valve 3|.

Securedto: the ends of therespec-ti-ve outlet conduitsZSl and29 are the respective inwardlyfacing radial cylindrical cup-members 32 and 32. Asshown in Figure 4, eachcup member is formed with. a conical seat 33 and the wall of the cup member is formedwith escape passages 34; Slidably mounted on the respective cup members32 and 32 are the respective shoe members 35 and 35", each shoe member being formed withan axial stud'iifislidably fitting"; Withinthe cup member and formedlwitha conicalv tip 31 fittingflithe'conical.seat"33; Rotatably mounted higher speedthan shaft 12L through the conduits 29 and 29and throughthe apertured cupsiw and' 32 Fluid enters housing [6 through the check valves 3| and 3|. As the speed of housing l4 and the fluid 45 carried therein builds up, the shoes 35 and 35' are rotated due to the torque exerted thereon by the fluid, and said shoes move outwardly by centrifugal force, whereby the cone tips 31 engage in their seats 33, closing off the cup members32 and 32'. This produces high resistance to the rotation of the pump gears 25 and 26, 26'. The back torque is transmitted through gears 24, 20 and 19 to gear 22, causing gear 22 and shaft H to rotate. Eventually gears 25, 25 and 26' become locked, whereby gear 24 becomes substantially fixed with respect to housing 14, gears 20 and I9, likewise become fixed with respect to said housing, and gear 22, meshing with gears l9, l likewise becomes fixed with respect to said housing, causing driven shaft l I to be directly coupled to driving shaft l2.

Should a heavy load be placed on shaft II, rotation of housing [4 is momentarily retarded, releasing the fluid torque and reducing the centrifugal pressure on said shoes. Fluid is then allowed to flow out of passages 34 allowing the pump gears 25 and 26, 26 to rotate and allowing gear 26 to rotate relative to housing I4 until sufficient torque has been furnished by driving shaft I! to restore the required speed of rotation of housing M to again close cup members 32, 32' and lock the pump gears. Under very heavy loads, the cup members 32, 32 will remain open allowing the driven shaft H to slip with respect to the driving shaft [2 without causing the engine connected to shaft I2 to stall.

When the driven shaft ll tends to rotate faster than the driving shaft I2, as when the vehicle employing the device is traveling down hill, gear 24 is still held fixed with respect to housing 14 since fluid cannot flow reversely through housing l6 because of the check valves 3!, 3|, and coasting of the vehicle is, therefore, prevented.

As shown in Figure 5, each check valve comprises a body formed with the main passage 4| communicating with the passage 30 or 30' in the pump housing wall. The valve body is formed with a transverse passage 42 communicating with passage 4| and leading to respective side conduits 43, 43 covered by apertured caps 44, 44. Positioned in the end portions of passage 42 are the balls 45, 45, normally held inwardly by coil springs 43, 45 acting between the balls and the apertured caps 44. In their inwardlybiased positions, the balls 45, 45 do not prevent flow of fluid into passage 42 from the caps 44. When the fiuid reverses in direction, the balls are seated over the bores of conduits 43, preventing outward flow of fluid from the valve.

While a specific embodiment of a combined torque changer and variable speed transmission has been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore, it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims.

What is claimed is:

1. In a variable speed transmission, a hollow cylindrical housing containing liquid and having first and second end walls, a drive shaft fixed axially to said first end wall, a driven shaft journalled axially through said second end wall and extending axially through said housing and journalled on said first end wall, a pump casing in said housing adjacent to said second end wall, said pump casing being traversed by said driven shaft, a sleeve journalled on said driven shaft within said housing, a pump gear keyed on said sleeve within said pump casing, other pump gears journalled in said pump casing and meshed with the first mentioned pump gear, planetary shafts mounted on said first housing endwall having planetary pinions thereon, a sun gear keyed on said driven shaft and meshed with said pinions, planetary gears fixed on said planetary shafts, a sun pinion fixed on said sleeve and meshed with said planetary gears, inlet check valve means providing only inlet communication between the interior of said housing and the interior of said pump casing, and normally open centrifugally closable outlet valve means providing only outlet communication between the interior of said pump casing and the interior of said housing.

2. In a variable speed transmission, a hollow cylindrical housing containing liquid and having first and second ends walls, a drive shaft fixed axially to said first end wall, a driven shaft journalled axially through said second end wall and extending axially through said housing and journalled. on said first end wall, a pump casing in said housing adjacent to said second end wall, said pump casing being traversed by said driven shaft, a sleeve journalled on said driven shaft within said housing, a pumpgear keyed on said sleeve within said pump casing, other pump gears journailed in said pump casing and meshed with the first mentioned pump gear, planetary shafts mounted on said first housing endwall having planetary pinions thereon, a sun gear keyed on said driven shaft and meshed with said pinions,

planetary gears fixed on said planetary shafts, a sun pinion fixed on said sleeve and meshed with said planetary gears, inlet check valve means providing only inlet communication between the interior of said housing and the interior of said pump casing, and normally open centrifugally closable outlet valve means providing only outlet communication between the interior of said pump casing and the interior of said housing, said outlet valve means comprising cylinders mounted on said pump casing having bores formed with valve seats, said cylinders being formed with outlet passages providing communication between the bores in the region of the valve seats and the interior of the housing, shoes mounted on said cylinders having pistons slidable in said bores and having tips for engagement with the seat to partially or fully close said outlet passages only when said shoes are displaced from normal positions by the action of centrifugal force, and means coupling said shoes together for coordinate movement.

PAUL H. MARSELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,658,021 Smith Jan. 31, 1928 1,820,083 Miller c Aug. 25, 1931 1,835,318 Miller Dec. 8, 1931 2,019,849 Foster Nov. 5, 1935 2,026,777 Dumble Jan. 7, 1936 2,102,131 Schmid Dec. 14, 1937 2,250,082 Robinson July 22, 1941 2,318,028 Thomas May 4, 1943 2,377,350 Marsh June 5, 1945 

